Move registration and deregistration of the main thread from
`isc_loopmgr_run()` into `isc__initialize()` / `isc__shutdown()`:
liburcu-qsbr fails an assertion if we try to use it from an
unregistered thread, and we need to be able to use it when the
event loops are not running.
Use `rcu_assign_pointer()` and `rcu_dereference()` in qp-trie
transactions so that they properly mark threads as online. The
RCU-protected pointer is no longer declared atomic because
liburcu does not (yet) use standard C atomics.
Fix the definition of `isc_qsbr_rcu_dereference()` to return
the referenced value, and to call the right function inside
liburcu.
Change the thread sanitizer suppressions to match any variant of
`rcu_*_barrier()`
Instead of writing complicated wrappers for every thread, move the
initialization back to isc_random unit and check whether the random seed
was initialized with a thread_local variable.
Ensure that isc_entropy_get() returns a non-zero seed.
This avoids problems with thread sanitizer tests getting stuck in an
infinite loop.
The `isc_trampoline` module had a lot of machinery to support stable
thread IDs for use by hazard pointers. But the hazard pointer code
is gone, and the `isc_loop` module now has its own per-loop thread
IDs.
The trampoline machinery seems over-complicated for its remaining
tasks, so move the per-thread initialization into `isc/thread.c`,
and delete the rest.
isc_bind9 was a global bool used to indicate whether the library
was being used internally by BIND or by an external caller. external
use is no longer supported, but the variable was retained for use
by dyndb, which needed it only when being built without libtool.
building without libtool is *also* no longer supported, so the variable
can go away.
As this code is on hot path (NSEC3) this introduces an additional
optimization of the EVP_MD API - instead of calling EVP_MD_CTX_new() on
every call to isc_iterated_hash(), we create two thread_local objects
for each thread - a basectx and mdctx, initialize basectx once and then
use EVP_MD_CTX_copy_ex() to flip the initialized state into mdctx. This
saves us couple more valuable microseconds from the isc_iterated_hash()
call.
The implicit algorithm fetch causes a lock contention and significant
slowdown for small input buffers. For more details, see:
https://github.com/openssl/openssl/issues/19612
Instead of using EVP_DigestInit_ex() initialize empty MD_CTX objects for
each algorithm and use EVP_MD_CTX_copy_ex() to initialize MD_CTX from a
static copy. Additionally avoid implicit algorithm fetching by using
EVP_MD_fetch() for OpenSSL 3.0.
The libxml2 library provides a way to replace the default allocator with
user supplied allocator (malloc, realloc, strdup and free).
Create a memory context specifically for libxml2 to allow tracking the
memory usage that has originated from within libxml2. This will provide
a separate memory context for libxml2 to track the allocations and when
shutting down the application it will check that all libxml2 allocations
were returned to the allocator.
Additionally, move the xmlInitParser() and xmlCleanupParser() calls from
bin/named/main.c to library constructor/destructor in libisc library.
The OpenSSL library provides a way to replace the default allocator with
user supplied allocator (malloc, realloc, and free).
Create a memory context specifically for OpenSSL to allow tracking the
memory usage that has originated from within OpenSSL. This will provide
a separate memory context for OpenSSL to track the allocations and when
shutting down the application it will check that all OpenSSL allocations
were returned to the allocator.
The libuv library provides a way to replace the default allocator with
user supplied allocator (malloc, realloc, calloc and free).
Create a memory context specifically for libuv to allow tracking the
memory usage that has originated from within libuv. This requires
libuv >= 1.38.0 which provides uv_library_shutdown() function that
assures no more allocations will be made.
Instead of using isc_once_do() on every isc_mutex_init() call, use the
global library constructor to initialize the default mutex attr
object (optionally with PTHREAD_MUTEX_ADAPTIVE_NP if supported) just
once when the library is loaded.
Instead of checking if we need to re-seed for every isc_random call,
seed the random number generator in the libisc global initializer
and the per-thread initializer.
This commit converts the license handling to adhere to the REUSE
specification. It specifically:
1. Adds used licnses to LICENSES/ directory
2. Add "isc" template for adding the copyright boilerplate
3. Changes all source files to include copyright and SPDX license
header, this includes all the C sources, documentation, zone files,
configuration files. There are notes in the doc/dev/copyrights file
on how to add correct headers to the new files.
4. Handle the rest that can't be modified via .reuse/dep5 file. The
binary (or otherwise unmodifiable) files could have license places
next to them in <foo>.license file, but this would lead to cluttered
repository and most of the files handled in the .reuse/dep5 file are
system test files.
Add library ctor and dtor for isc_os compilation unit which initializes
the numbers of the CPUs and also checks whether L1 cacheline size is
really 64 if the sysconf() call is available.
The previous versions of BIND 9 exported its internal libraries so that
they can be used by third-party applications more easily. Certain
library functions were altered from specific BIND-only behavior to more
generic behavior when used by other applications.
This commit removes the function isc_lib_register() that was used by
external applications to enable the functionality.
It was discovered that on some platforms (f.e. Alpine Linux with MUSL)
the result of isc_os_ncpus() call differ when called before and after we
drop privileges. This commit changes the isc_os_ncpus() call to cache
the result from the first call and thus always return the same value
during the runtime of the named. The first call to isc_os_ncpus() is
made as soon as possible on the library initalization.
On some platforms, the __attribute__ constructor and destructor won't
take priorities and the compilation failed. On such platform would be
macOS. For this reason, the constructor/destructor in the libisc was
reworked to not use priorities, but have a single constructor and
destructor that calls the appropriate routines in correct order.
This commit removes the extra priority because it's now not needed and
it also breaks a compilation on macOS with GCC 10.
util.h requires ISC_CONSTRUCTOR definition, which depends on config.h
inclusion. It does not include it from isc/util.h (or any other header).
Using isc/util.h fails hard when isc/util.h is used without including
bind's config.h.
Move the check to c file, where ISC_CONSTRUCTOR is used. Ensure config.h
is included there.
The current isc_hp API uses internal tid_v variable that gets
incremented for each new thread using hazard pointers. This tid_v
variable is then used as a index to global shared table with hazard
pointers state. Since the tid_v is only incremented and never
decremented the table could overflow very quickly if we create set of
threads for short period of time, they finish the work and cease to
exist. Then we create identical set of threads and so on and so on.
This is not a problem for a normal `named` operation as the set of
threads is stable, but the problematic place are the unit tests where we
test network manager or other APIs (task, timer) that create threads.
This commits adds a thin wrapper around any function called from
isc_thread_create() that adds unique-but-reusable small digit thread id
that can be used as index to f.e. hazard pointer tables. The trampoline
wrapper ensures that the thread ids will be reused, so the highest
thread_id number doesn't grow indefinitely when threads are created and
destroyed and then created again. This fixes the hazard pointer table
overflow on machines with many cores. [GL #2396]
Instead of calling isc_tls_initialize()/isc_tls_destroy() explicitly use
gcc/clang attributes on POSIX and DLLMain on Windows to initialize and
shutdown OpenSSL library.
This resolves the issue when isc_nm_create() / isc_nm_destroy() was
called multiple times and it would call OpenSSL library destructors from
isc_nm_destroy().
At the same time, since we now have introduced the ctor/dtor for libisc,
this commit moves the isc_mem API initialization (the list of the
contexts) and changes the isc_mem_checkdestroyed() to schedule the
checking of memory context on library unload instead of executing the
code immediately.
3760. [bug] Improve SIT with native PKCS#11 and on Windows.
[RT #35433]
3759. [port] Enable delve on Windows. [RT #35441]
3758. [port] Enable export library APIs on windows. [RT #35382]
